Volcano Watch: Kilauea activity update for March 1, 2018

On the south rim of Pu‘u ‘Ō‘ō, on Kīlauea’s East Rift Zone, an HVO geologist surrounded by thick steam and gas performs regular upkeep to the west pit time-lapse camera. This camera was relocated again at the end of January due to continued subsidence and instability in its previous location. The camera’s field of view encompasses the entire rim of the west pit and the surrounding area (see time-lapse camera images). Photo taken Friday, February 23, 2018 courtesy of U.S. Geological Survey

A telephoto image of the spattering lava pond contained within the west pit at Pu‘u ‘Ō‘ō. Wind-blown gas and steam reduced visibility. Photo taken Friday, February 23, 2018 courtesy of U.S. Geological Survey

This west pit time-lapse image was taken on February 19 at 6:20 am showing changes in the area since the previous image (taken on January 31). On February 10 at 8:21 am (exact time based on seismic data) a large portion of the northeastern rim of the west pit (right side of glowing pit), collapsed. Prior to and during the rim collapse, the adjacent ground also subsided. Photo taken Friday, February 23, 2018 courtesy of U.S. Geological Survey

A single image from the time-lapse camera at Pu‘u ‘Ō‘ō, with the spattering lava pond producing a bright glow from within the west pit (center of photo). This image was taken on January 31 at 6:15 am, shortly after the lunar eclipse ended (moon visible in the upper left corner). Photo taken Friday, February 23, 2018 courtesy of U.S. Geological Survey

This past week, Kīlauea Volcano’s summit lava lake level fluctuated between about 36 to 42 m (118 to 138 ft) below the vent rim. On the East Rift Zone, the 61g lava flow remained active downslope of Pu‘u ‘Ō‘ō, with scattered breakouts on Pulama pali. No lava is entering the ocean. The 61g flows do not pose an immediate threat to nearby communities.

Mauna Loa Volcano is not erupting. A few small-magnitude earthquakes occurred beneath the volcano, primarily on its west flank, at depths shallower than 13 km (8 mi). GPS and InSAR measurements continue to show slow deformation related to inflation of a magma reservoir beneath the summit and upper Southwest Rift Zone. Rates of inflation in the past few months have decreased compared to rates of the past year. It is uncertain if these lower rates will persist or pick up again in the near future. No significant changes in volcanic gas emissions were measured.

Time-lapse image movie from a research camera positioned on Holei Pali, looking east towards Lava Flow 61G and Kalapana. February 22, 2018 to March 1, 2018. Images courtesy of USGS/HVO

Time-lapse movie from a camera positioned on the southeast flank of Puʻu ʻŌʻō, looking toward the active flow advancing to the southeast. The breakout point is at the left edge of the image, and the mid-field skyline at the right is roughly coincident with the top of the pali. February 22, 2018 to March 1, 2018. Images courtesy of USGS/HVO

This map shows recent changes to Kīlauea’s East Rift Zone lava flow field. The area of the active flow field as of January 30, 2018 is shown in pink, while widening and advancement of the active flow as of February 20, 2018 is shown in red. Older Puʻu ʻŌʻō lava flows (1983–2016) are shown in gray. The yellow line is the trace of the active lava tubes. The Kamokuna ocean entry is inactive. The blue lines over the Puʻu ʻŌʻō flow field are steepest-descent paths calculated from a 2013 digital elevation model (DEM), while the blue lines on the rest of the map are steepest-descent paths calculated from a 1983 DEM (for calculation details, see pubs.usgs.gov/of/2007/1264/). Steepest-descent path analysis is based on the assumption that the DEM perfectly represents the earth’s surface. DEMs, however, are not perfect, so the blue lines on this map can be used to infer only approximate flow paths. The base map is a partly transparent 1:24,000-scale USGS digital topographic map draped over the 1983 10-m digital elevation model (DEM)